There was a clarification comment on this cooling system overhaul parts list over here today:

Quote:

Originally Posted by BM109R

This is also my next DIY project. I've already replaced all the tensioners and belts recently so I only need the WP, thermostat, hoses and, expansion tank, fan, fan clutch radiator. My question is should I also include the vent hose that goes from expansion tank to radiator? I do not see that listed in any of the recommended parts list. I have attached a picture. The part number is 17111427156.

Quote:

Originally Posted by BM109R

Just saw the hose I was checking for on the list. On realoem it is called vent hose while on cn90's list it is the bypass hose.

__________________

Please read the suggested threads, where the best always add value to those threads, either by pictures or by descriptions, so the next person with the same problem stands on your shoulders.
See also: E39 Bestlinks & How to easily find what you need